Savannah courier. (Savannah, Tenn.) 1885-1979, 1887-10-13
FIRE AND WATER.
A New Theory Concerning the Power OF
the Latter Over Flames.

A New Theory Concerning the Power OF
the Latter Over Flames.
have often been puzzled to answer
for myself why water extinguishes fire.
A great many people say that it is be-
cause the water and its steam so COM
pletely envelop the burning material
as to exclude oxygen, and thus, the
fire must stop. This seems to me an
insufficient. If not entirely erroneous
reason. My reason is this: We know
that nothing will burn q. e. unite
with oxygen with the evolution of
heat and light) unless and until it has
been raised to a given temperature.
Thus: Sodium burns at ordinary tem-
peratures-about so degrees if dry-the
gas of ordinary kerosene at about ITO
degrees or less, and so on. Why do we
tip a piece of stick with sulphur and
then with phosphorus to make matchesP
Because, while wood must have quite
high temperature. phosphorus will
burn at comparatively low tempera-
ture-so low that the heat developed
by slight friction will ignite it. The
phosphorus makes enough heat to lg-
mite the sulphur, but not enough to
start the wood. The sulphur in burn
ing makes heat enough to ignite the
wood. But l will ask another qucs-
tion: Wood ashes are white. Why
is the remaining end of the
match, and often most of it,
black in colorP Is it not because
carbon being black, and the wood be-
ing composed of carbon and compound
substances, which are very intiamma-
BILE, the latter burn, but, this generally
answering our purpose, do not gener-
ate enough heat to oxidize the former?
This seems TO me the reason, the car
bon remaining. Thus promising, and
showing that carbon, which forms the
bulk of wood Gas well as of paper. cot
ton, ETC., } requires to be very hot be-
fore it will unite with the oxygen, we
may consider the water for moment.
Perhaps the easiest way to make my
point clear is to take a common illus
tration. Every one knows that if one
puts kettle of water on ht ated stove,
he must wait a long time for it to be-
come boiling hot, or a temperature OF
PIP degrees Fahr Now, if he should
put the same amount of quicksilver on
by the side of the water, the latter
would reach 2l2 degrees far sooner.
Why is thisp 1t is because the water
takes up large amount of heat which
is there in the water, but which the
thermometer does not index. Now if,
after reaching 212 degrees, he sets
them off, the mercury will reach the
temperature of the surrounding all
much more rapidly. Now. suppose he
wished to boil all the water away, tC
evaporale it, in that case remembering
that in passing from water to steam the
temperature is not raised even degree
nor any fraction of one, could he no
make it all evaporate instantly
by raising the temperature q little
We all know he could not; that the fir'
has degree of heat several hundred
degrees higher, but the kettle must re
main long time, while the wate
very gradually goes off as steam. VIII,
so? Because the water, in becomin!
steam, must take into itself larg,
amount of heat not shown by the ther
mometer, and as the heat can be addet
only gradually the formation of steam
is slow. Now, in the large amount o
heat which water can take up and tn
fact that ordinary inflammables mus
be raised to high temperature in or
} der to burn, we have the cause o
} water putting out fire. Put burn
ing match into a very small drop Q
watef and il is extinguished because O
} the very large amount of heat take
from the match in reducing the waite
to steam. which reduces the tempera
, ture of the match to far below 2l2 dc
: grees, or at least that far, if there
, water enough, and so the carbon am
; its compounds forming the wood wi
, no longer unite with the oxygen of th
air. For the same reason a hot iro
thrust into water is cooled, and waite
/ sprinkled on the floor cools the air, tn
: heat of evaporation in the latter cas-
: coming from the air itself, thus COO
: ing it. Now, if we could find a fluit
: very plentiful, which requires muc
more heat than water to make it boi
evidently we could put large fires OF
much more readily.-B. B. James,
So. Louis Globe Democrat.